Prehosp Emerg Care. 2020 Mar-Apr;24(2):220-231. doi: 10.1080/10903127.2019.1624900. Epub 2019 Jul 10.
A multi-tiered response (MTR) system has been controversial in terms of cost-effectiveness and outcome improvement. It remains uncertain whether a cardiopulmonary resuscitation (CPR)-targeted tiered response system is associated with better outcomes after out-of-hospital cardiac arrest (OHCA). This study aimed to investigate the effect of an MTR on OHCA outcomes. A natural experimental study was conducted for resuscitation-attempted adult OHCAs. The MTR system was implemented in Korea by the National Fire Agency in 2015 across the country where the single-tiered ambulance response system existed. The MTR program had the following 3 components: 1) detection of OHCA by dispatcher, 2) dispatch of ambulance or fire engine in addition to routine dispatch of ambulance, and 3) performance of team CPR. The study period of 2015-2016 was divided by 6 months (phases I [reference], II, III, and IV). The endpoints were prehospital defibrillation, prehospital return of spontaneous circulation (PROSC), survival to discharge and good neurological recovery. A multivariable logistic regression analysis was performed to evaluate the effect of the intervention, and adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were calculated, adjusting for potential confounders. A total of 32,663 eligible OHCA cases were evaluated during the study period. As the intervention program spread, the MTR with ambulance increased (from 7.0% in phase I to 53.7% in phase IV, for trend < 0.01). During the study period, prehospital defibrillation increased from 23.6% in phase I to 26.9% in phase IV and the study outcome was improved from 7.4 to 12.6% for PROSC, from 6.7 to 9.1% for survival to discharge, and from 4.5 to 5.8% for good neurological outcome ( for trend < 0.01 for all). Compared with phase I, the AORs (95% CI) of phase IV were 1.16 (1.08-1.25) for prehospital defibrillation, 1.82 (1.63-2.04) for PROSC, 1.37 (1.21-1.56) for survival to discharge, and 1.23 (1.06-1.43) for good neurological outcome. The nationwide implementation of a multi-tiered response system for OHCA was associated with increased prehospital defibrillation and improved outcomes of OHCA patients.
多层级反应（MTR）系统在成本效益和结果改善方面一直存在争议。心肺复苏（CPR）为目标的分层反应系统是否与院外心脏骤停（OHCA）后的更好结果相关仍不确定。本研究旨在探讨 MTR 对 OHCA 结局的影响。
一项针对复苏尝试的成年 OHCA 的自然实验研究。2015 年，韩国国家消防局在全国范围内实施了 MTR 系统，该系统采用了单一层次的救护车反应系统。MTR 计划有以下 3 个组成部分：1）调度员检测 OHCA，2）除常规调度救护车外，调度救护车或消防车，3）团队 CPR 执行。2015-2016 年的研究期间分为 6 个月（第 I 期[参考]、第 II 期、第 III 期和第 IV 期）。终点是院前除颤、院前自主循环恢复（PROSC）、出院生存率和良好的神经恢复。进行多变量逻辑回归分析评估干预效果，并计算调整后的优势比（AOR）及其 95%置信区间（CI），以调整潜在混杂因素。
在研究期间，共评估了 32663 例符合条件的 OHCA 病例。随着干预计划的传播，带有救护车的 MTR 增加（从第 I 期的 7.0%增加到第 IV 期的 53.7%，趋势<0.01）。在研究期间，院前除颤从第 I 期的 23.6%增加到第 IV 期的 26.9%，PROSC 的研究结果从 7.4%提高到 12.6%，出院生存率从 6.7%提高到 9.1%，良好的神经结局从 4.5%提高到 5.8%（趋势<0.01 ）。与第 I 期相比，第 IV 期的 AOR（95%CI）分别为院前除颤 1.16（1.08-1.25）、PROSC 1.82（1.63-2.04）、出院生存率 1.37（1.21-1.56）和良好的神经结局 1.23（1.06-1.43）。
全国范围内实施 OHCA 多层级反应系统与院前除颤增加和 OHCA 患者结局改善有关。
